PDA

View Full Version : Creating UV coordinates after sculpting?


mcscher
01-27-2010, 04:16 AM
Hi there,

I have a question on creating UVs after having finished a sculpture in ZBrush.

Lets assume you have made a high poly and highly detailed concept design in ZBrush (with no UV layout) that got approved and needs to be retopologized for production to be animation and rigging friendly.

How would you create the UV layout for the retopologized sculpt having in mind to use a normal map being saved out of ZBrush afterwards?

tin-tin
01-27-2010, 11:01 AM
I would retopo and layout the uv's then bake normal maps from the zbrush model in any 3d app, or import your retopo model in zbrush and zproject.

mcscher
01-27-2010, 11:26 AM
I would retopo and layout the uv's then bake normal maps from the zbrush model in any 3d app

I always used the ZMapper for normal maps and this required to switch to the lowest geometry lvl of the same model to generate the normal map to. Does this still work with the retopologized model? It has a different topology after all compared to the original model. I assume the normal map will no longer work since it is based on a different topology (original <-> retop).

I definitely will have to try the zproject method, sounds interesting. Thanks for the tipp so far!

musashidan
01-29-2010, 10:28 AM
If you import the UVed retop to ZB and Zproject the original highpoly sculpt your subdiv levels will be reconstructed and in R3 you just create your normal map from the rollout. No more arsing about in Zmapper. :D

Zeternal
01-30-2010, 08:53 PM
Hi there,

I have a question on creating UVs after having finished a sculpture in ZBrush.

Lets assume you have made a high poly and highly detailed concept design in ZBrush (with no UV layout) that got approved and needs to be retopologized for production to be animation and rigging friendly.

How would you create the UV layout for the retopologized sculpt having in mind to use a normal map being saved out of ZBrush afterwards?

First off it really depends upon the Zbrush version you are currently using, as methods vary between 3.1 and the 3.5 versions. If you are using any of the 3.5 versions you will need to reduce you Subdivisions down to the lowest level, and export an .obj.

Take the .obj into whatever unwrapper you use, be it Maya or UV Layout which does the best job in my opinion and unwrap the geometry.

Once this is complete resave as an .obj and export out the geometry with set UV's.

Reopen the original mesh and make sure your still on the lowest subdivision level and save a morph target. This is located in the tools > morph target > StoreMT.

Import the .obj on top of the mesh, and it will ask you if you want to save high resolution details, click yes.

Switch your morph target tools > morph target > switch. Return to highest subdivision level and that's it. Once your textures and normal/displacement maps are reapplied you can export a .ma with your texture network already set up using version 3.5 If you are not using 3.5 there are several tutorials on how to do this on this site.

Hope this helps!

mcscher
01-30-2010, 09:59 PM
Thanks Zeternal for your little tutorial. It definatelly cleared some issues I'm having.

The one thing that still isn't clear to me is applying the highres detail of a zsphere based mesh onto a retopologized mesh. The poly layout (not UV layout) might be totaly different to the mesh I did the details on. I guess that's when the zproject is supposed to come in right?

oh and yes, I'm still using ZBrush 3.12

CGTalk Moderation
01-30-2010, 09:59 PM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.